US Senator Frank Lautenberg (D-NJ) passed away this morning.

From NorthJersey.com (The Record):

Frank R. Lautenberg, who rose from a poor Paterson boyhood to become a multimillionaire businessman and New Jersey’s longest-serving U.S. senator, died  Monday at 89 of viral pneumonia, his office said.

The oldest member of the Senate and its last World War II veteran, Lautenberg had struggled with health problems since late last year, when he missed several weeks of votes because of what he said was flu and bronchitis.

This means that Republican Governor Chris Christie will be appointing a replacement until an election for the full six-year term takes place.

So the question on the minds of many – especially those of us in NJ – who will Christie pick?

It’s not so simple, really.  The Fix explains:

The popular first-term governor could, as is often the case in situations like these, choose to nominate a close ally from his own party. If he goes that route, a few obvious possibilities are state Sen. Tom Kean Jr., the party’s 2006 Senate nominee; Lt. Gov. Kim Guadagno; and 2012 nominee Joe Kyrillos, a close Christie ally whom the GOP nominated for the Senate in 2012.

Of course, it’s possible — though less likely — that Christie would appoint a Democrat to the seat. He is campaigning as a bipartisan governor in a very blue state, after all. Tapping a Democrat would be seen as a major stroke of bipartisanship. Replacing a Democrat with a Democrat and then saying the voters should decide what happens next in November would no doubt be very well-received by Democrats and moderates.

But such a move would be politically perilous for Christie when it comes to his own party. It would run the risk of angering Republicans, the last thing Christie needs if he has any designs on running for president in 2016. He has already stoked some concern among conservatives by embracing President Obama in the aftermath of Hurricane Sandy.

And then, there’s Cory Booker.

Booker had long been viewed as a potential Christie opponent leading up to this year, but opted to run for the Senate instead. Christie and Booker have a good relationship, which they have poked fun at over the years. If there is a Democrat Christie might be tempted to appoint, Booker would be that Democrat.

Being in NJ myself, I can tell you, it’s a very liberal state here where even many Republican voters are far more moderate.  This is no clean choice for Christie – either way, he ends up alienating someone.  It will be interesting to see which way he goes.